Swift - Get Object in Array By Property [duplicate]

Question

I'm new to Swift and I am having a few problems with retrieving an object in an array by property.

Please note, I am using Swift 2.0.

I have the following array;

//Dummy Data prior to database call:
static var listPoses = [
    YogaPose(id: 1, title: "Pose1", description: "This is a Description 1", difficulty: Enums.Difficulty.Beginner, imageURL: "Images/Blah1"),
    YogaPose(id: 2, title: "Pose2", description: "This is a Description 2", difficulty: Enums.Difficulty.Advanced, imageURL: "Images/Blah2"),
    YogaPose(id: 3, title: "Pose3", description: "This is a Description 3", difficulty: Enums.Difficulty.Intermediate, imageURL: "Images/Blah3"),
    YogaPose(id: 3, title: "Hello World", description: "This is a Description 3", difficulty: Enums.Difficulty.Intermediate, imageURL: "Images/Blah3")
] 

I now have a method that I'd like to return an object by Id. Can someone please advise how I would do so ... e.g. where listPose.Id === Id;

 //Returns a single YogaPose By Id:
class func GetPosesById(Id: Int) -> YogaPose{


    if(listPoses.count > 0){
        return listPoses() ...
    }

}

Answer 1

So Swift provides your a way to filter a list of object based on the condition you want.

In this case, you will need to use filter function:

class func GetPosesById(Id: Int) -> YogaPose?{
    return listPoses.filter({ $0.id == Id }).first
}

Basically, the filter function will loop thru the entire listPoses and returns you a [YogaPose]. The code ({$0.id == Id}) is your condition and $0 means the current object in the loop.

I also change your function signature a bit

class func GetPosesById(Id: Int) -> YogaPose

To

class func GetPosesById(Id: Int) -> YogaPose?

because the first property is an optional object which you will need to unwrap later